Choose the correct statement for the complex ${\left[\mathrm{Al}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$:

Since ${\mathrm{NH}}_3$ is a weak field ligand and, due to ${\mathrm{d}}^2{\mathrm{sp}}^3$ hybridizationelectrons in the third orbitals are therefore left unpaired, ${\left[\mathrm{Cr}{\left({\mathrm{NH}}_3\right)}_6\right]}^{3+}$ has a paramagnetic characteristic. While ${\left[\mathrm{Al}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$ is diamagnetic. Hence, option B is correct.